Lubricating oil, etc.



I Patented July 6,1943

to The Standard Oil Company, Cleveland, Ohio, a corporation of Ohio.

' No Drawing. Application September 28, 1940,

Serial-No. 358,930

6 Claims.

Mineral oils subjected to usage in contact with metal surfaces and more or less elevated temperature are prone to. undergo considerable changes in body and also form more or less deposit. Various agents have been proposed and are in use in efforts at mitigation of these tendencies, but quite commonly if some advantage is gained in one respect there is produced some offsetting factor which may bequite disadvantageous under some conditions. I have found that the combinations set forth more in detail here- 1 inafter, have an outstanding utility for oils under drastic usages, and surprisingly, the combinational results are out of all proportion to results with the agents applied individually.

To the accomplishment of the foregoing and related ends, the invention, then, comprises thefeatures hereinafter fully described, and particularly pointed out in the claims, the following description setting forth in detail certain illustrative embodiments of the invention, these being indicative however, of but a few of the various ways in which the principle of the invention may be employed.

Depending upon the particular duty in view, the oil may be of various character and source, and for instance may be of viscosity 45 to 200 sec. Saybolt Universal at 210 F., and of Mid- Continent or other source. With it is incorporated a phenyl methane derivative and a salt of an oxy-sulphur acid, i. e. alkyl sulphuric or sulphonic acid of the general formula R.SO1L.R', wherein R'is an alkyl or halogen-substituted alkyl radical, n is 3 or 4, and R is a base (e. g. lead, tin, aluminum, magnesium or alkaline earth metal, sodium or alkali metal, ammonia or an amine). The alkyl sulphuric acid salts are particularly advantageous. Mixtures of alkyl sulphates and sulphonates may be employed, and mixtures are particularly easily had in practice. The compounds derivable from cocoanut oil fatty acids by separation and reduction and sulphonation are especially desirable, and of these the lauryl compounds are outstanding. The amount of the phenyl methane derivative may be .01 per cent to 2.0 per cent and the alkyl salt 0.1 per cent to 1.0 per cent, depending upon the oil and the particular usage in view. Illustrative of the phenyl methanes are diamino phenyl methanes, triamino phenyl methanes, as tetra methyl diamino diphenyl methane, tetra ethyl diamino diphenyl methane, tetra benzyl diamino diphenyl methane, tetra-methyl triamino diphenyl methane, tetra amino diphenyl methane, tetra methyl diamino triphenyl methane, tetra ethyl diamino is the maximum with difdrfiary oil.

'phate.

triphenyl methane, etc., and illustrative of the alkyl salts are aluminum octyl sulphate, sodium lauryl sulphate, ammonium hexyl sulphate, lead lauryl sulphate, magnesium lauryl sulphate, amyl ammonium cetyl sulphate, methyl ammonium ricinoleo sulphate, calcium lauryl sulphate, etc. Correspondingly also the sulphonates. And, the combinations involve such a phenyl methane derivative and a salt of alkyl sulphuric or sulphonic acid, as for instance tetra ethyl diamino diphenyl methane and sodium lauryl sulphate, tetra benzyl diamino diphenyl methane and calcium octyl sulphonate, tetra methyl triamino diphenyl methane and'aluminum lauryl sulphate, tetra methyl diamino triphenyl methane and sodium lauryl sulphate, etc.

As an example: With a lubricating oil of S. A. E. 20 Mid-Continent stock there is incorporated 0.25 per cent of tetra methyl diamino diphenyl methane and 0.5 per cent of sodium lauryl sul- This lubricant in an Ethyl Gasoline Corporation test engine running under full load for a twenty hour continuous period, with sump temperature 300 F. and jacket temperature 212"- F., showed a viscosity increase of 133, sludge formation 0.5, lacquer formation 0.00, piston rating 0, and total demerit rating 4.6. (The piston rating is on a scale of 10, from 0 which represents the degree of cleanness or lack of accumulation characteristic ainew'piston, while 10 V W The demerit rating is the sum of the-"sludge, acid number, piston rating, and one-tenth of the viscosity increase.) In contrast, the S. A. E. 20 oil without the additions, run under the same standard conditions, showed a viscosity increase of 413, sludge formation 4.0 per cent, lacquer formation 80.0

Other modes of applying the principle oftheinvention may be employed, change being made as regards the details described, provided the fea- 3. A mineral oil containing a small amount of l triamino diphenyl methane and an octyl sulphate.

4. A mineral oil containing a small amount of a phenyl amino methane and a lauryl sulphate.

5. A mineral oil containing a small amount of a phenyl amino methane and an alkyl sulphate.

6. A mineral oil containing a small amount of a phenyl amino methane and a salt of an ozw-sulphur acid, of the formula R.SOflR', wherein R is an alkyl or halogen-substituted alkyl radical, n is 3 or 4, and R is a metal, ammonia or amine.

JOHN M. MUSSELMAN. 

